Hogwarts as far as we know it the only wizarding school in England, and every indication points to Lockhart being British, how is that none of the adults would have recognized him, as a student, I'm sure he must have been a complete flop as a teenager as well, wouldn't they suspect he's a fraud?
--- I don't think Lockhart stood out as a student, not many teachers remember the students that pass, well I don't think he has a significant quality or that he was particularly good at something or a subject to be remembered. Plus many students have gone to Hogwarts, it is hard for a professor to remember a student that is somewhat minor, Dumbledore is remembered because he was the best student to ever attend Hogwarts, Voldemort is remembered because he is the most evil wizard in the whole wizarding world, professors such as madame hooch wouldn't remember Hermione for instance, she was never good at flying or quidditch, but I'm sure she would remember Harry or Neville for what happened to them (Harry being the youngest seeker and Neville because he fell). So I think you should be at least good at a subject or be troublesome to be remembered..
If Petunia or Dudley turned out to be a "late blooming witch/ wizard, do you think Vernon would have divorced his wife, or disowned his son? What would have been his reaction to both cases?
--- Well, I thought that Petunia is the late blooming witch actually, but she didn't turn out like that. Dudley doesn't stand a chance or he cannot even dream into becoming a wizard.
Call me crazy but, I don't think Vernon would be angry, I think his reaction might be different to what we expect, all these years he seems like as if he hates magic and wizards, but who knows what's deep inside of him, who knows if he ever wished to have married Lily instead of Petunia, I mean he might even be proud if Dudley was a wizard. I think he would change his point of views and perspectives to suit his new family's life style..
There are obviously vampires in, Harry Potter even if Rowling didn't really touch up on the subject. Do you think that if a wizard becomes a vampire they lose their magic?
--- Hmm, that is interesting..
Well, no a wizard is a wizard becoming a vampire wouldn't make him lose his magical abilities. There are wizards who happen to be werewolves and still they are wizards, so I don't think so..
Do YOU think that the body of someone with a Horcrux ages?
O_o ...What an odd question you are asking, does your body age Lord Voldemort ??..
--- Hmm, yes I think so, but in a very slow pace, just like in the lord of the rings, Frodo's appearance didn't change much, he didn't have a leap of change like most people do through 17 years I think .. But he still changed, I think he still grew a bit.
Age has nothing to do with being immortal or making Horcruxes, because you don't split your physical appearance you split your soul, the changes that happen occur in your soul not your body, so whatever magic that is going to happen it will happen to your soul, your soul is the only thing that is going to be preserved not your appearance, and you can't just stick to one appearance and stay that way forever, you will age until you can't age further more, besides Lord Voldemort was old he was 81 or 71 ?? so he was already wrinkled lol.. :P although, I don't suppose that he is wrinkled, he is snake like and snakes don't wrinkle..
Great questions.. ^_^